Aecio Neves, a business-friendly centrist, is to go head to head against the incumbent President Dilma Rousseff in the race for the country's top job after a last minute surge propelled him past the favorite to a place in the October 26 run-off.

Neves, of the Brazilian Socialist Democrat Party (PSDB), overtook environmentalist Marina Silva, who had been predicted to be the eventual winner of the presidency, to come second in Sunday's first round with 33.6 percent to her 21.3 percent. The centre-left Rousseff won, as expected, with 41.6 percent of the vote.

Just days ago, few would have bet on Neves. All polls had suggested a race for the win between Rousseff, of the Workers' Party (PT), and Silva, of the Brazilian Socialist Party (PSB).

Silva entered the race after former-PSB candidate Eduardo Campos died unexpectedly in a plane crash, and her powerful backstory as a former illiterate rubber-tapper quickly pushed her forward in the polls, showing her beating Neves in a first round, and Rousseff in a second.

But attack ads from the PT suggesting Silva, an idealist who declared that hers would be a "new politics," lacked the backbone and political capital to cut deals and govern effectively in Brazil's unwieldy congress, seemed to have had an effect.

"Changes of her party, lack of consistency with her previous position on environmental and behavioral issues, conservative alliances, inconsistency between a liberal economic program and progressive social program," Sonia Fleury, a political scientist from Rio's Getulio Vargas Foundation, said of Silva's vulnerabilities. "Her opponents exploited these weaknesses, and her advocacy of a "new politics" failed to convince the streets."

Some argue too that Silva had squandered opportunities with an unwillingness to attack back and a series of missteps. One such fumble saw her offer, and then retract, her support for gay marriage, allowing the PT to characterise her as a flip-flopper in thrall to a powerful Pentecostal religious lobby.

Meanwhile, the focus on Silva took the heat off Neves, Fleury said, sparing him too much criticism and allowing him to quietly build on a strong record as governor of Minas Gerais, Brazil's second most populous state, where he cut the state deficit, took a 45 percent salary cut and linked public servants' salaries to performance.

To voters frustrated by Brazil's stubbornly stagnating economy and persistent inflation, this was attractive.

"[Aecio] is the best option for the fiscal health of the country," said Marcelo de Souza Teixeira, 26, a civil servant in the finance ministry. "He's promised to liberalise the country a little, economically, which I think is really important, and to cut public spending and shrink the number of ministries."

"The economy is the most important issue of this election, for me," Teixeira added.

Marcos Troyjo, director of the BRICLab at Columbia University, was optimistic about Brazil's chances of economy recovery with Neves at the helm.

"If Aécio is elected the economic horizon will improve and current skepticism would be reverted," Troyjo said. "He heads a well-structured political party and his economic team is made of well-versed and experienced economists."

Rousseff has remained towards the top of the polls despite difficulties kickstarting the economy and a wave of countrywide protests last year that at their peak brought more than a million Brazilians onto the streets. Many still admire her record in social programs that have seen tens of millions of Brazilians lifted from abject poverty.

"A country needs to go forward, not backwards, and that's the way we've been going with Dilma with people moving from being hungry, moving from poverty," said Esdras Santana, 33, a banker.

Polls released on the eve of the election suggested that Rousseff would win a second round against Neves, with 48 percent to his 42 percent. But that gap seems rather more narrow when a 2 percent margin of error is taken into account.

Fleury says that most of SIlva's supporters are unlikely to transfer their votes to Neves. Many of those voters lean left, and saw in Silva the potential for a focus on issues of health, education and environment, as well as a likely continuation of Rousseff's social policies.

"I think Marina represents the best of Dilma, the social programs, but also would bring about a change that would diminish the amount of corruption," said Camila Gonçalves Moura, 30, a lawyer from Brasília.

Even so, Neves may benefit from fatigue with the PT, which has been in power for 12 years.

"There is a feeling of exhaustion with the PT," Fleury said, "after the issue of allegations of corruption, relentlessly explored by the media."

Fleury added that it was a "shame" that Silva had not succeeded in reaching the second round with Rousseff, who fought as a guerrilla against Brazil's military dictatorship.

"It would have been a luxury to have seen two women [contesting the presidency] who built their biographies fighting for democracy," she added.